Apparatus for expressing milk

ABSTRACT

A device for expressing milk from one or more breasts has at least one, and preferably two expressors and a pump. The expressors each have a cup for fitting on the breasts and a cup outlet to which a vacuum created by the pump can be connected. In use, the vacuum expresses the milk from the breast. The device has a vacuum adjustment and a vacuum release on each expressor. In this manner, the vacuum can be individually adjusted and released at the expressors. The pump includes a movable diaphragm in a chamber. The diaphragm is oscillated back and forth by a linear actuator motor such as a stepper motor. The motor has a shaft which moves back and forth axially, for direct linkage to the diaphragm, so that the size and weight of the pump are reduced. The expressors have a removable cap and removable cup assembly, and the cup assembly has a positively sealed liner, for easy disassembly and cleaning.

This is a continuation-in-part of provisional application Ser. No.60/140,902 filed Jun. 23, 1999.

FIELD OF THE INVENTION

This invention relates to apparatus for extracting natural milk, andmore particularly, to breast pumps which are convenient and comfortableto use.

BACKGROUND OF THE INVENTION

Pumps for expressing milk from breasts are well-known. One known breastpump is disclosed in Whittlestone U.S. Pat. No. 4,607,596.

The Whittlestone patent discloses a breast pump having two milkcollectors connected to a pump which applies both a vacuum and pulsatingpressure to the breasts to extract milk. The pulsating pressure massagesthe breast to stimulate milk production, and the vacuum secures the milkcollectors to the breasts and helps draw the milk and collect it.However, the vacuum at the two collectors can only be adjusted at thepump, and cannot be individually adjusted. This can create discomfortfor the user if one breast is more sensitive than the other, or respondsto stimulation differently than the other. Thus, there is a need forbreast pumps having individual control of two collectors, which is morecomfortable for the user.

The Whittlestone patent does not disclose a vacuum release for thecollectors. As a result, when the device is turned off, the vacuum isbroken by pulling the collectors from the breasts, or waiting for thevacuum to dissipate in order to remove the collectors. This isinconvenient and sometimes uncomfortable. Thus, there is a need forbreast pumps having a vacuum release, preferably in a convenientlocation such as the collectors themselves.

In the Whittlestone device, milk from the two collectors is commonlydrawn into a first collection vessel, and then a second collectionvessel. The milk is drawn through vacuum lines, though, which makescleaning difficult. Moreover, the milk collecting vessels are reusable,and require frequent and thorough cleaning. Accordingly, there is a needfor breast pumps which are more sanitary and easier to clean than theWhittlestone device.

The Whittleson patent discloses a breast cup having a housing, arelatively soft inner ring or donut, and a flexible liner. The linerwraps around the outlet of the cup, and a bung is inserted into the cupoutlet to pass the vacuum and milk. At the inlet side, the liner issimply folded over the outside of the housing. This design haslimitations. The liner is not accurately aligned and reliably sealed onthe inlet side, so moisture and other contaminants can get inside theliner, which is undesirable. At the outlet, the liner can collapsearound the entire breast, including the tip of the nipple, which can beuncomfortable and can cause unnecessary trauma. Accordingly, there is aneed for breast pumps having cups which better fix the liner to thehousing. There is also a need for breast pump cups which protect atleast the end of the nipple from discomfort due to pulsating pressure.

The breast pump disclosed in the Whittlestone patent is a diaphragm pumpoperated by an electric motor. Rotation of the motor shaft is translatedinto back and forth action by a somewhat large and cumbersome linkagewhich moves the diaphragm. This adds not only size but weight to thepump, as well. This is a problem because storage and portability aredesirable to breast pump users. Thus, there is a need for breast pumpswhich are lighter and smaller than known devices.

Accordingly, one object of this invention is to provide new and improvedapparatus for extracting milk from breasts.

Another object is to provide new and improved breast pumps which aremore convenient and comfortable to use.

Another object is to provide new and improved breast pumps havingcollectors with individual vacuum adjustments for each collector, and atleast one vacuum release.

Still a further object is to provide new and improved breast pumps whichare more sanitary, easy to clean and easy to disassemble and assemble.

Another object is to provide new and improved breast pumps which aremore comfortable to use.

Yet another object is to provide new and improved breast pumps which arerelatively light, compact and portable.

SUMMARY OF THE INVENTION

A device for expressing milk from one or both breasts has at least onemilk collector and a pump. Preferably, the device has first and secondcollectors (also called expressors), so that both breasts can be milkedsimultaneously. Each expresser has a cup assembly which fits on thebreast, a pulsation port to which a supply of pressurized pulsating airis connected, and a vacuum port to which a vacuum supply is connected.The pulsating air and vacuum are created by the pump. In use, pulsatingair massages the breast and stimulates milk production, while the vacuumsecures the collector on the breast and helps express the milk from thebreast.

A vacuum adjustment is provided on each collector, and a vacuum releaseis provided on one, and preferably each collector. In this manner, thevacuum can be individually adjusted, and easily released.

The collectors also include a cap and manifold which direct the vacuumand pressure, a cup assembly which is preferably press fit onto themanifold, a collection vessel secured to the bottom of the manifold, anda one-way check valve or the like between the manifold and thecollection vessel. After passing through the vacuum adjustment, thevacuum is directed through the cap and manifold, collection vessel andcup assembly so that the milk is drawn into the collector with little orno milk entering the vacuum lines to the pump. A filter may be providedfor extra isolation of the vacuum pump and vacuum lines, if desired.

The cup assembly includes a bell housing, a relatively soft donut shapedpad, and a flexible liner, preferably made of silicone. The liner issecured to the inlet side of the cup assembly by a locking type ofattachment, and extends around the bottom or lower end of the case,where it is secured by another locking press fit configuration.

The bottom end of the case fits into a receptacle in the manifold. Thereceptacle has a boss which extends into the cup assembly by a desireddistance. This boss prevents the liner from collapsing around the end ofthe nipple during use.

The collector can be easily disassembled and cleaned in a dishwasher orthe like, by removing the collection vessel and using or storing themilk, removing the cap and vacuum adjustment/release valve, and thenremoving the cup assembly. The cup assembly can be cleaned withoutremoving the liner, if desired, or the liner can be removed and cleanedseparately, or replaced. A cleaning cap can be placed over the airpulsation port of the cup assembly when the cup assembly is cleaned inits assembled condition, to prevent water from entering the spacebetween the liner and the case.

The manifold, cap and valve can also be washed. The cup assembly can beeasily reassembled after cleaning by reinserting the cup assembly in themanifold, reattaching the cap to the manifold and cup assembly, andsecuring another collection vessel to the bottom of the manifold, withthe check valve.

The pump includes a movable diaphragm in a chamber. The diaphragm isoscillated back and forth by a linear actuator motor such as a steppermotor. The motor preferably has a shaft which does not rotate, but movesback and forth axially. The shaft of the motor is directly or nearlydirectly linked to the diaphragm, which eliminates complex andcumbersome linkage components, reducing the size and weight of the pump.

BRIEF DESCRIPTION OF THE DRAWINGS

The above mentioned and other features of this invention and the mannerof obtaining them will become more apparent, and the invention itselfwill be best understood with reference to the following description ofan embodiment of the invention taken in conjunction with theaccompanying drawings, in which:

FIG. 1 is a partially cut-away perspective view of apparatus made inaccordance with the principles of this invention;

FIG. 2 is a milk collector used in the apparatus of FIG. 1, shown incross-section;

FIG. 3 is a top view of the milk collector of FIG. 2, taken along lines3—3 in FIG. 2;

FIG. 4 is an exploded view of a cup assembly used in the collector ofFIG. 2;

FIG. 5 is an exploded view of the collector of FIG. 2;

FIG. 6 is a cut-away view of the collector of FIG. 2, showing the linerin a collapsed condition;

FIG. 7 is a cut-away view of a vacuum adjustment/release assembly in thecollector of FIG. 2;

FIG. 8 is a cut-away view of an alternate embodiment of the pump used inthe apparatus of FIG. 1;

FIG. 9 is a block diagram of a control system for the apparatus of FIG.1;

FIGS. 10 and 11 are diagrams of an alternate embodiment of the diaphragmused in the pump in the apparatus of FIG. 1;

FIG. 12 is a perspective view of another embodiment of the collectingvessel of FIG. 2 as a flow-through bag;

FIG. 13 is a perspective view of the annular ring of FIG. 12;

FIG. 14 is an exploded perspective view of the flow-through bagconnection mechanism; and

FIG. 15 is a cross-sectional side view of the flow-through bag as anintegral unit.

DETAILED DESCRIPTION

Referring to FIG. 1, apparatus 10 is provided for expressing milk fromone breast, or from two breasts simultaneously. The apparatus 10includes a first collector or expressor 12 and a second expressor 14. Apump 16 is connected to both expressors 12, 14 through vacuum lines 18,20, and air pressure lines 22, 24.

The pump 16 creates a vacuum which engages the breasts, and contributesto drawing the milk from the breasts. The pump also creates pressurepulsation around the areola and some or all of the nipple, as will beseen. The pump 16 can be powered by line voltage, a battery, manually orthe like.

The expressors 12, 14 are shown in greater detail in FIGS. 2 and 3. Eachexpresser includes a manifold 26, a cup assembly 28 which fits over abreast, a cap 30, a vacuum adjustment release valve assembly 32, acollection vessel 34 and a valve 36. The collection vessel can be abottle made of plastic-like material or the like, or a bag, as will beseen, as can be oriented at an obtuse angle with respect to the cupassembly, as shown.

The manifold 26 includes an opening 38 which is preferably threaded, sothat a collection vessel such as a plastic milk bottle can be threadedlysecured to the manifold 26, with the valve 36. The valve 36 ispreferably a one-way check valve such as a duck bill valve or the like.

A vacuum enters the expressor through a vacuum port 40 in the assembly32. After passing through a port 42 in the cap 30, the vacuum enters avacuum path in the manifold 26 through an opening 44 in the top of themanifold. The vacuum is drawn through an internal orifice 46 to theopening 38, which is beneath the port 42 and the cup assembly 28. Thevacuum tends to close the valve 36, which prevents a substantial buildupof vacuum in the collection vessel 34.

The vacuum is drawn from the opening 38 cup assembly opening or milkoutlet port 48 through a channel 50. When milk is drawn from the breast,the milk passes through the channel 50 under the force created by thevacuum, but most of the milk drops into the valve 36 through the forceof gravity, and does not enter the orifice 46. When sufficient milkcollects in the valve 36, the weight of the milk forces the valve open,which releases the milk into the collection vessel 34. In this manner,the milk is collected without contaminating the vacuum lines 18, 20(FIG. 1).

The cup assembly 28 has an milk inlet port 52 in addition to the outletport 48. The components of the cup assembly 28 include a bell housing54, a donut shaped pad 56, and a flexible liner 58, shown disassembledin FIG. 4. The cup assembly 28 also has an air pressure pulsation port60 which allows air to enter a space 62 between the case bell housing 54and the liner 58.

The cup assembly 28 is assembled by placing the donut shaped pad 56 inthe housing 54 as shown, and does not need further securement. The pad56 is preferably made of a suitable foam material which is sized to fitsnugly in the housing 54. However, the pad 56 can be easily removed byplacing a finger through the opening in the ring and pulling the ringout.

The liner 58 is installed in the cup assembly 28 by securing an end 63to the liner 58 in a groove 64 formed in the housing 54 (FIGS. 2, 3 and4). The end 63 and groove 64 are shaped to provide locking press fittype of securement.

The liner 58 extends from the groove 64 over and around the pad 56 andinside of the housing 54 to a bottom end 66 of the housing 54. An end 68of the liner 58 is inserted into a groove 70 near the end 68 forsecurement in a press fit fashion. The liner 58 can be any suitableshape, including the shape shown in FIG. 2, which includes a relativelynarrow section 72 near the inlet opening 52, and a wider section 74between the section 72 and the outlet end 48 of the cup assembly 28.This shape places more pressure around the areola region of the breast,while placing less pressure on the nipple itself.

By sealing the liner to the case at both ends, the assembly can bewashed without taking the liner off, if a cleaning cap 75 is placed overthe pressure inlet 45 (FIG. 4).

The cup assembly 28 can be press fit into a circular groove 76 in themanifold 26, seen in FIG. 5. The groove 76 is formed by an outside wall78 and an inside boss 80. The boss 80 can extend outwardly as far asdesired, and can be any suitable shape, such as circular, triangular,square, rectangular, elliptical, hexagonal, etc. Since the boss 80 ishollow and prevents the liner 43 from collapsing under outside airpressure, the boss 80 protects any part of the nipple which is insidethe boss from pressure when the liner is collapsed, as seen in FIG. 6.

The cap 30 (FIGS. 2, 3 and 5) includes an air pressure/pulsation channel82, which extends from an air pressure inlet 84 in the assembly 32 tothe port 60. The cap 30 can be press fit over the manifold opening 44and the cup assembly air pressure/pulsation port 60, and can be easilyremoved. When installed, the cap 30 further secures the cup assembly inthe manifold, but both the cap and the manifold can be removed withouttools for cleaning purposes. The cap itself can be easily cleaned in adishwasher or the like by removing the vacuum adjustment/releaseassembly 32, if desired, which is preferably press fit into the cap 30.The cap may have a filter (not shown) to further prevent liquids or thelike from entering the vacuum lines and the pump.

The vacuum adjustment assembly 32 includes a housing 86, a thumbwheel88, a pin 90, and a cap 92, shown in FIG. 7. The thumbwheel 88 hasthreads 94 which adjustably secure the thumbwheel 88 in an orifice 96 inthe housing 86. A threaded insert 97 can be secured in the orifice 96for this purpose. An O-ring 98 maintains the vacuum in the line 40.

An end 100 of the pin 28 at least partially enters the vacuum port 40 toregulate the vacuum. The vacuum to the expressors is cut off when theend 100 is pressed against a valve seat 101.

The cap 92 is secured to the pin 90 by adhesive or the like. The pin 90is preferably biased away from the port 40 by a spring 102, whichpresses the cap 92 away from the thumbwheel 88 and normally opens thevacuum port 40 when the pin 90 is released. The port 40 is opened to adesired extent by turning the thumbwheel 88 until a suitable vacuumlevel is set. A mylar or other suitable gasket 103 between the end 100and the thumbwheel 88 prevents undesired loss of vacuum through theassembly 32.

The spring 102 allows the pin 90 to be pressed down so that it releasesthe vacuum in the cup assemblies 28 when the seal created by the gasket103 is broken. The vacuum at both expressors 12, 14 can be released bypressing the vacuum release on one or both of the expressors.

Referring again to FIG. 1, the pump 16 has two halves 104, 106 securedtogether by screws or the like 108 to form a chamber 110. The screws 108also secure a movable diaphragm 112 in place. The diaphragm 112 dividesthe chamber 110 into two halves 110 a, 110 b.

The diaphragm 112 is oscillated in a back and forth manner by a motor114. The motor can be secured to the housing by bolts 116 or the like.

The motor 114 can be a stepper motor, which is one form of a linearactuator, which has a shaft 118. The shaft 118 moves in and out of themotor 114 in the axial direction without rotation. The shaft 118 isthreaded, and is moved by a rotating threaded ring 120, which is similarto a nut. Rotation of the ring 120 moves the shaft 118 linearly. In thismanner, the shaft 118 can move the diaphragm 112 back and forthessentially directly, without large, complex linkages.

The distal end of the shaft 118 can be guided by an opening 122 in anend cap 124. The end cap 124 is secured by bolts 126.

The pump 16 also has vacuum outlets 128, 130 in the chamber 110, onopposite sides of the diaphragm 112. The vacuum lines 18, 20 areconnected to the vacuum outlets 128, 130 through a common vacuum line132, which accesses the lines 18, 20 equally and simultaneously througha port 134. Check valves such as duck bill valves 136, 138 control thevacuum and pumping operation, and exhaust valves 140, 142 release thepressure created in the chamber halves 110 a, 110 b by the movement ofthe diaphragm 112. However, some of the pressure generated by thediaphragm is transmitted through the pressure lines 22, 24 to thecollectors 12, 14. The pressure forces the liners 58 against the breasts(see FIG. 6), which further stimulates release of milk. While the vacuumis fairly continuous, though, the pressure pulsates. In fact, when thediaphragm moves away from a pressure line 22, 24, air is drawn out and apartial vacuum can be created.

The device is light weight, portable and compact because large motorlinkages are eliminated. Wear is also reduced by simplifying the powertrain in this manner. The motor 114 can be any suitable device whichcreates a fairly self-contained drive system which is relatively smallin size and fairly quiet. In fact, the motor can be an ordinary motor114 with a threaded rotating shaft 146, as seen in FIG. 8. In thatembodiment, a fixed ring 148 is attached to the diaphragm. The ring 148is also threaded, so when the shaft 146 rotates forward and backwards,the diaphragm 112 moves back and forth.

The motor can be controlled in any suitable manner, such as the controlsystem 150 shown in FIG. 9. An application specific integrated circuitor the like has a microprocessor 152 and a ROM 154, programmed to causea motor driver 156 to set the desired rate of rotation and the directionof rotation of the motor. The rotation rate, as well as the timing ofthe back and forth motion of the diaphragm, can be controlled in thismanner.

The diaphragm 112 can be any suitable configuration, such as that shownin FIG. 1, which features a flat stiff middle section flanked by softcorrugations. Another design is shown in FIGS. 10 and 11, where adiaphragm 158 has a plurality of rings 160 joined by corrugations 162.

FIG. 12 is a perspective view of another embodiment of a collectionvessel as a flow-through bag 1000, which can be used to eliminate theneed for sterilization of the unit as assembled in FIG. 2. The bagportion can be molded with a grain which facilitates easy removal. Theflow-through bag 1000 includes a channel portion 1010 and amilk-collecting bag portion 1015. The channel portion 1010 includes aflexible neck 1035 defining an internal channel. The flexible neck 1035is configured to be inserted into the milk outlet 38, through thevacuum/milk communication pipe 50, through the inside of the liner 58,and out the breast cup assembly 28. The channel portion 1010 preferablyincludes a breast cup overlay (1315, FIG. 15) similar to that of thelines 58 at the distal end of the neck 1035 to overlay the breast cupassembly 28 at the inlet 52. The breast cup overlay 1315 may bemaintained over the breast cup assembly 28 using the locking mechanismpreviously described, a tie wire, rubber band or nothing. The upperportion (1320, FIG. 15) of the neck 1010 is preferably shaped similar tothe flexible liner 58, so that no buckling of material occurs. Thechannel portion 1035 may include removable tape 1040 for clamping theneck 1035 and powder (not shown) to facilitate the feeding of theflexible neck 1035 through the manifold 26 and breast cup assembly 28.

A vacuum spout and one-way valve molding 1045 is sealed within theproximate end of the internal channel defined by the neck 1035. Themolding 1045 effectively divides the internal channel into a firstinternal channel portion which is fed through the breast cup assembly 28and a second internal channel portion which forms a skirt 1065 about themolding 1045.

The vacuum spout and one-way valve molding 1045 is shown in greaterdetail in FIG. 13. The molding 1045 includes an annular ring 1055 sealedwithin the proximate end of the internal channel defined by the neck1035. The annular ring 1055 forms a vacuum/milk passage (aperture) 1060therethrough. The molding 1045 further includes a vacuum spout 1050coupling the second internal channel portion to an environment externalthe neck 1035. The vacuum spout 1050 enables vacuum pressure from thevacuum pipe 46 to flow through the vacuum spout 1050, through theannular ring 1055, and back up the vacuum/milk passage 1060 to thebreast cup assembly 28.

The molding 1045 also includes two rigid plastic prongs 1070 directedaway from the neck 1035 for encouraging duckbill check valve action withthe flexible skirt 1065 that overhangs the annular ring 1055.Accordingly, vacuum pressure exerted through the vacuum spout 1050causes the flexible skirt 1065 to close about the two rigid prongs 1070.Milk can still flow down the internal channel defined by the neck 1035,through the vacuum/milk passage 1060, through the one-way valve 1065,and into the bag portion 1005. Alternatively, the molding 1045 canalternatively include a ball valve, a duck-bill check valve like valve36, or any other one-way valve.

The bag portion 1005 includes a milk-collecting possibly disposable bag1015, having a label area 1020 for a banner and/or note area for writinginformation such as date and time of expression. The bag portion 1005preferably includes a bag sealing mechanism 1075 for enablingwater-proof closure of the bag, and a water-and-air-tight grain 1030 forenabling easy removal of the disposable bag 1015. Alternatively, the bag1015 can be cut with scissors. Although not shown in FIG. 12, a clampingmechanism (see FIG. 14) holds the annular ring 1055 within and againstthe milk-collecting bag 1015.

FIG. 14 is a perspective view of an example attachment for theflow-through bag 1000. As illustrated, the neck 1035 is inserted up thevacuum/milk communication pipe 50 of the manifold 26. The collectingvessel attachment mechanism, illustrated as threading 1215, is shown asdangling out of the manifold 26.

In the embodiment illustrated in FIG. 14, the top end 1210 of thedisposable bag 1005 is inserted through a clamping mechanism 1205 andfolded over. The clamping mechanism 1205 preferably includes threading(not shown) to engage the threading 1215 of the manifold 26. When theclamping mechanism 1205 is attached to the threading 1215, the vacuumspout 1050 preferably is directed up the vertical vacuum pipe 46, theannular ring 1055 abuts the edge of the threading 1215, and the molding1045 forces the channel portion 1010 against the disposable bag 1005thereby creating a waterproof seal and supporting the disposable bag1005.

FIG. 15 illustrates another embodiment as a integral bag, neck andmolding unit 1300. As shown, the neck 1035 and bag 1015 are a singleunit. The molding 1055 is sealed within the unit 1300 to form avacuum/milk aperture 1060 dividing the internal channel into a neckchannel portion 1325 and a bag channel portion 1330. The molding alsoincludes a vacuum aperture 1310 from a point external the unit 1300 tothe bag channel portion 1330. The molding 1055 also includes a one-wayvalve, illustrated as a duckbill check valve 1305. Although not shown, aconnection mechanism is used to maintain the molding 1055 against thevertical vacuum tunnel 46 of the manifold 26, so that vacuum pressurecan be exerted through the vacuum aperture 1310, through the vacuum/milkaperture 1060 and onto the breast. Because the bag is a single unit, theconnection mechanism need not maintain a water-and-air-tight sealbetween the two bag portions of FIGS. 12–14.

In use, power is applied to the pump 16, and the expressors 12, 14 areplaced over the breasts. The vacuum created by the pump 16 secures theexpressors 12, 14 on the breasts and helps draw milk from the breasts.The pulsating air massages the breast to stimulate milk production, andreduces the amount of vacuum needed to collect the milk.

The vacuum in each expressor 12, 14 can be adjusted individually byturning the thumbwheels 88, without pressing pins 90 down. To releasethe vacuum, one or both of the pins 90 is pressed down. The device canbe easily disassembled without tools, cleaned and reassembled.

The many advantages of this invention are now apparent. Breast pumpingis more comfortable because the user can individually control the vacuumsupplied to each breast. Release is also more comfortable because thevacuum can be released before removal. Cleaning is more convenientbecause milk does not enter the vacuum lines. Moreover, the entirecollector can be easily disassembled for cleaning and reassembledwithout tools. The bosses in the expressors protect the end of thenipple from irritation, which is comfortable. Moreover, the entire pumpis small, lightweight and relatively quiet.

While the principles of the invention have been described above inconnection with a specific apparatus and applications, it is to beunderstood that this description is made only by way of example and notas a limitation on the scope of the invention. For example, variousaspects of the invention could be used to milk animals, as well ashumans.

1. Apparatus for expressing milk from a breast comprising: a milkcollector unit having a manifold assembly, the manifold assembly havinga vacuum path and a pulsating pressure path, a collection vesseloperatively connected to said vacuum path, a cup assembly, said cupassembly having a housing having an inlet and an outlet, a pad locatedin the input end of said housing, and a liner extending from saidhousing inlet to said housing outlet, said liner being secured to saidhousing to form a space between said housing and said liner which is incommunication with said pulsating pressure path, pressure in saidpulsating path moving said liner within said housing, and the manifoldassembly having a hollow boss which extends into the outlet within theliner and increases the area for breast extension during milkexpression.
 2. The apparatus of claim 1 wherein said manifold assemblyincludes a manifold to which said collection vessel is secured, and aremovable cap, said cup assembly being secured to said manifold assemblyby both said manifold and said cap.
 3. The apparatus of claim 2 whereinsaid vacuum path begins in said cap and passes through said manifold tosaid cup assembly, and said pulsating pressure path passes through saidcap to a pressure port in said cup assembly, said pressure port being incommunication with said space between said housing and said liner.